Gene redundancy

[2] Gene knockout is a method utilized in some studies aiming to characterize the maintenance and fitness effects functional overlap.

Classical models of maintenance propose that duplicated genes may be conserved to various extents in genomes due to their ability to compensate for deleterious loss of function mutations.

Beyond these classical models, researchers continue to explore the mechanisms by which redundant genes are maintained and evolve.

Retroposition is when the mRNA transcript of a gene is reverse transcribed back into DNA and inserted into the genome at a different location.

[11] As the genome replicates over many generations, the redundant gene's function will most likely evolve due to Genetic drift.

[12] In the event that genetic drift maintains the variants, the gene may accumulate mutations that change the overall function.

[11] During nonfunctionalization, or degeneration/gene loss, one copy of the duplicated gene acquires mutations that render it inactive or silent.

[16] The backup hypothesis proposes that redundant genes remain in the genome as a sort of "back-up plan".

In this case, the redundant part of the gene remains in the genome due to the proximity to the area that codes for the unique function.

For example, at the University of Michigan, a study provides the theory that redundant genes are maintained in the genome by reduced expression.

Currently, there are three ways to detect paralogs in a known genomic sequence: simple homology (FASTA), gene family evolution (TreeFam) and orthology (eggNOG v3).

Researchers often construct phylogenies and utilize microarrays to compare the structures of genomes to identify redundancy.

[18] Before performing more laborious analyses of redundant genes, researchers typically test for functionality by comparing open reading frame length and the rates between silent and non-silent mutations.

Using online databases like the Genome Browser at UCSC, researchers can look for homology in the sequence of their gene of interest.

The mode of duplication by which redundancy occurs has been found to impact the classifications in breast cancer disposition genes.

One particular family that is involved in the initial event of odor perception has been found to be highly conserved throughout all of vertebrate evolution.

[23] For example, Strout et al.[24] have shown that tandem duplication events, likely via homologous recombination, are linked to acute myeloid leukemia.

The partial duplication of the ALL1 (MLL) gene is a genetic defect has been found in patients with acute myeloid leukemia.